Moistureproof construction for shafts



Feb. 21, 1950 T. CYMMER MOISTUREPROOF CONSTRUCTION FOR SHAFTS Filed July9, 1945 1N VEN TOR. THOMAS CYMMEIZ.

I LW

A TTO/ZNE X Patented F eb. 21, 195

UNITED STATES PATENT MOISTUREPROOF CO SHAF NSTRUCTION FOR TS ThomasCymmer, Jersey City, N. J. Application July 9, 1945, Serial No. 603,995

1 Claim.

(Granted under the act of March 3, 1883, as

amended April 30, 1928; 370

This invention relates to a moistureproof device for transmitting rotarymotion through a barrier or partition.

It is essential that many devices such as some radio and navigationalequipment, be completely moistureproof. As these devices are externallycontrolled or adjusted by means of knobs and dials, considerabledifficulty has been encountered in making them moistureproof. Packingglands around the shafts have previously been employed but they have notexcluded all moisture.

The present invention provides a gas and moistureproof seal bytransmitting rotary motion through an imperforate member.

An object of this invention is to provide a device for transmittingrotary motion while excluding all moisture.

Another object is to provide a device for transmitting rotary motionthrough an imperforate member.

Further objects and advantages of this invention, as well as itsconstruction, arrangement and operation, will be apparent from thefollowing description and claim in connection with the accompanyingdrawing, in which Fig. 1 is a central, vertical, cross-sectional view ofa device embodying the present invention,

Fig. 2 is a cross-sectional view taken on the line 2--2 of Fig. 1.

The front panel of the instrument is provided with an inwardlyprojecting portion 2 having an aperture 3 therethrough. Mounted in theaperture 3 is a shaft 5 having an enlarged portion 5 forming a shoulderat which abuts the projecting portion 2 of the instrument panel I. Aknob or dial l is fixedly secured to the end of the shaft 4 projectingoutwardly of the panel I. A pin 8 prevents rotation of the dial 7 withrespect to the shaft i. The end of the shaft extending inside the panell is provided with a preferably circular member 9 eccentrically mountedon shaft 4. The circular member 9 may be made integral with the shaft 4or may be produced separately and then secured thereon.

A metal bellows It is positioned over the circular member 9 with theskirt portion thereof soldered or otherwise sealed to the panel I aboutthe inwardly projecting portion '2 and shaft 4 so as to provide an airtight connection therewith. The bellows is preferably made of lightmetal so that the pleated portion thereof may be distorted or bent asthe member 9 rotates about the shaft 4. secured within the end of themetal bellows l0, preferably by soldering, is a wearing socket ll shapedto fit over the circular member 9. A wearing cap I2 is positioned overthe outer end of the bellows l0 and is also secured to the bellowspreferably by soldering.

Mounted on the inner face of panel I is a casing I3 having a bearingportion M in which shaft I5 rotates. Shaft I5 is so mount-ed that it isin alignment with the shaft 4. There is eccentrically mounted on theshaft I5 within the casing 13 a circular cup-shaped member IE which fitsover the wearing cap !2 mounted on the end of the bellows.

With this construction no moisture can pass through the rotarytransmission device to the inside of the equipment with which it isused.

In operation, rotation of the dial or knob I rotates the shaft 4 and thecircular member 9 eccentrically mounted on the inner end thereof. As themember 9 rotates, it slides around the inner end of the bellows anddisplaces the same about the shaft 4. This in turn causes theeccentrically mounted cupped-shaped member Hi to be rotated with theeccentrically mounted member 9.

Modifications and changes can be made in the embodiment of thisinvention without departing from the spirit and scope of the invention.

The invention described herein may be manufactured and used by or forthe Government of the United States of America for governmental purposeswithout the payment of any royalties thereon or therefor.

What is claimed is:

A moistureproof device for transmitting rotary motion through a barriercomprising a rotatable shaft projecting through said barrier, a circularmember eccentrically mounted on said shaft, a metal bellows positionedover said member for being secured to said barrier, a wearing socketsecured to the inside of said bellows and fitting over said member, awearing cap positioned over said wearing socket and said bellows andsecured to said bellows, a second shaft outside said bellows alignedwith said first shaft, a circular cup-shaped member eccentricallymounted on said second shaft and fitting over said wearing cap, wherebyrotation of one shaft causes rotation of the other.

THOMAS CYMMER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,436,444 Holmes Nov. 21, 19221,736,974 King Nov. 26, 1929 2,119,955 Litton June '7, 1938 FOREIGNPATENTS Number Country Date 92,097 Sweden of 1938 98,132 Switzerland of1923

